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I've been trying to get the SSD1306 device working with my library, only come to find out that the way the framebuffer keeps its memory is bizarre.
Basically, it's monochrome, so 8 pixels are packed into a byte. But they're packed *vertically*
It appears as though the screen is divided into vertical banks, 1 byte high that hold 8 rows, but those are arranged left to right.
Whoever designed it that way should be punished.
Severely.
Anyway, I figured out a way to change the memory addressing mode, and on top of doing that I flip the whole screen from landscape to portrait and address it that way, and I get some sort of sane horizontal bitmapping, even if my screen is now 64x128 instead of 128x64
However, that mapping mode isn't quite working the way I'd expect.
SSD1306, error - YouTube[^]
I had to post a 3 second video instead of a pic because of the camera->screen refresh interference causing tearing (you'll see what i mean)
I tried to draw a 64x128 hatched rectangle with a solid white border.
That hatched square is supposed to take up the entire screen. It does not, and the border if you look closely, does not appear along the left edge of the screen like it should, and the other side appears but is offset by several pixels as if the screen is wrapping around and offset by like 20 or so.
I can't decipher the datasheet on this addressing mode. It's not clear at all, but it's the closest mode to sanity I've managed to find.
My other option is to do what the other drivers do, and create a special frame buffer in the weird format, then blt everything to that, and force you to call an update() method explicitly to draw it to the screen.
I wanted you to be able to create a bitmap and then use that as your framebuffer, and not have an extra hidden framebuffer stealing RAM.
But in order to do that I need to know how this elephanting memory addressing scheme works, and why it's giving me this output.
I hate datasheets.
Real programmers use butterflies
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I wrote a bitmap font renderer for such a display many years ago, the strange pixel format meant rearranging the font data so it could be rendered quickly at any position with bit shifts and bitwise or's on a seriously underpowered cpu.
That was a fun challenge.
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I didn't design for this. Who makes framebuffers this way? It's just ... meh
Real programmers use butterflies
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It is a well-known "fact" among hardware designers that software is free. The reasoning goes like that: given that software is written only once for any number of devices, its cost is vanishingly small compared to any gate on silicon. So they don't bat an eyelid when they invent stuff like write-only registers (hey, software can keep a copy of the register) or convoluted memory paging schemes (hey, software can change the paging register every 100 instructions or so).
Those of us who have to debug programs with a scope suffer the consequences 
Mircea
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The write only thing over serial i could live with if not for the other thing. But don't mess with me from both directions at once.
These modules these days are almost entirely sold to MCU builders. MCUs don't have spare cycles and RAM for this nonsense. 
Real programmers use butterflies
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Quote: My other option is to do what the other drivers do
This would definitely work. Have a look at what existing drivers do and infer the addressing mode. We are lucky there is Arduino with all the related drivers around.
"In testa che avete, Signor di Ceprano?"
-- Rigoletto
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Does Bruce Willis keep playing the same roles because old habits Die Hard?
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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What the hack else can he do? Supposedly the Whole Nine Yards an action figure but Armageddon tired of seeing the same faces in the same roles.
| Ravings en masse^ |
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| "The difference between genius and stupidity is that genius has its limits." - Albert Einstein | | "If you are searching for perfection in others, then you seek disappointment. If you seek perfection in yourself, then you will find failure." - Balboos HaGadol Mar 2010 |
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Most of his roles are just Pulp Fiction anyway. Call it my Sixth Sense, but his typecasting as an action hero is gonna be Hard to Kill.
Real programmers use butterflies
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Just coat him in RED pain and move on. He will always be dying hard with a vengence
To err is human to really elephant it up you need a computer
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Sometimes he does go to sin city to do some moonlighting.
"the debugger doesn't tell me anything because this code compiles just fine" - random QA comment
"Facebook is where you tell lies to your friends. Twitter is where you tell the truth to strangers." - chriselst
"I don't drink any more... then again, I don't drink any less." - Mike Mullikins uncle
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'Whach you talking bout Willis' for?
If you can't laugh at yourself - ask me and I will do it for you.
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That's his career - one disaster after another.
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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Here we are again! That's not a clue btw!
Angle for King to get agricultural tool. (9)
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Angle PITCH
for FOR
King K
to get agricultural tool.
PITCHFORK
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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"I didn't mention the bats - he'd see them soon enough" - Hunter S Thompson - RIP
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Yes, absolutely bang on. You are up for tomorrow.
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... Introducing the latest and greatest: Nanacoin![^]
Still makes more sense than Bitcoin ... 
"I have no idea what I did, but I'm taking full credit for it." - ThisOldTony
"Common sense is so rare these days, it should be classified as a super power" - Random T-shirt
AntiTwitter: @DalekDave is now a follower!
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So we have money backed by gold, and money backed by government, and money backed by greed, and now money backed by Nana...
Not an easy choice... 
"The only place where Success comes before Work is in the dictionary." Vidal Sassoon, 1928 - 2012
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At least if Nana cheats you, the money stays in the family. 
Freedom is the freedom to say that two plus two make four. If that is granted, all else follows.
-- 6079 Smith W.
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OriginalGriff wrote: Still makes more sense than Bitcoin
Maybe it's my age but, yes, I'm with you.  In fact, pretty much everything makes more sense than Bitcoin!  I'm just waiting for the little boy to shout: "Look! The King isn't wearing any clothes!".
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There is probably more debt in the world than there is money, the financial world trades on paper and derivatives valued at multiple times the worldwide GDP... and Bitcoin is the thing that trips your trust meter? 
If you can't laugh at yourself - ask me and I will do it for you.
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DRHuff wrote: and Bitcoin is the thing that trips your trust meter?
It's not the only thing. Anything involving IT/Computers is on my list! As are politicians, the press, the police, bankers, advertising & marketing people, managers, estate agents.... Yeh, I have a big list! 
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I hope 100 Shreddies would = 1 Nana
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